1. Field
The present invention relates to a vane pump device.
2. Description of Related Art
For example, in a vane pump disclosed in JP-A-2013-50067, discharge ports are respectively provided at two positions which face each other in a diameter direction passing through the center of a rotor, one of the two discharge ports is referred to as a main discharge port, and the other is referred to as a sub-discharge port. The main discharge port is connected to a discharge passage and a discharge outlet so as to normally supply discharged oil to a fluid device. The sub-discharge port communicates with the discharge passage and the discharge outlet via a communication passage.
JP-A-2011-196302 discloses a vane pump including a switching valve that switches between a full discharge position at which a working fluid is suctioned and discharged in both main and sub regions and a half-discharge position at which the working fluid is suctioned and discharged only in the main region. The switching valve switches the pressure of the working fluid introduced to vanes in the sub region such that the vanes retract to the rotor and move away from the inner circumferential cam surface of the cam ring at the half-discharge position.
In a vane pump device including a pump unit that discharges a working fluid from multiple discharge ports, and a housing that accommodates the pump unit, it is considered that the amounts of a working fluid discharged from one pump chamber of the pump unit via discharge ports are different from each other. Even if the amounts of the working fluid discharged via the discharge ports of the pump unit are different from each other, it is desirable to implement a configuration in which all the working fluid can be smoothly discharged to the outside from the housing.